A friend noted this:
Hundreds of millions of years of “deep time” is frequently cited as the saving feature for the profound improbability of each step of the Stairway [to Life]. Yet time is only an ally of a slow constructive process if degradation is ignored. As a useful analogy, imagine the very slow construction of a house. The earthmovers clear the site and dig a foundation. The masons arrive one thousand years later and find a dense forest with a slight depression in one area. Nevertheless, they do their best to lay the foundation. After another thousand years, the carpenters arrive and find a dense forest and sparse remnants of cement and cinder block. Undaunted they construct the wooden frame of a house. The roofers arrive a thousand years later to find a dense forest and almost no detectable remnant of any prior construction effort. Clearly, a house can never be constructed in such a manner.
For abiogenesis, the situation is far worse. Here, the process of ascending the twelve steps of Figure 6 is thought to have occurred over hundreds of millions of years. The sources of energy that are thought to be needed for construction of larger and more complex molecules (i.e., thermal, radiation, ultraviolet light, electricity, etc.) are all quite capable of breaking larger molecules into smaller molecules. The thermodynamic drive to increase entropy can only be overcome by the continuous infusion of energy combined with the proper “engine” to convert the energy into a building process rather than a destructive process.
—The Stairway to Life: An Origin-Of-Life Reality Check, Change Laura Tan and Rob Stadler, p. 82.
You may also wish to read: The Science Fictions series at your fingertips – origin of life What we do and don’t know about the origin of life.